Method and apparatus for maintaining level plow when angling

ABSTRACT

A support assembly that includes first and second frame components may be used to support a plow blade to a vehicle. The first frame component may have a first end defining a first pivot axis about which the plow blade pivots when it is moved side-to-side. The second frame component may have a first end that defines a second pivot axis about which the second frame component, the first frame component and the plow blade pivot when the plow blade is raised or lowered. A second end of the first frame component may be pivotally attached to a second end of the second frame component about a third pivot axis. The first frame component and the plow blade may automatically pivot together about the third pivot axis to maintain the plow blade in a level orientation even when the plow blade is both raised and moved side-to-side.

This application claims priority to U.S. Ser. No. 61/614,594, entitledMETHOD AND APPARATUS FOR MAINTAINING LEVEL PLOW WHEN ANGLING, filed Mar.23, 2012, which is incorporated herein by reference.

I. BACKGROUND OF THE INVENTION

This invention pertains to the art of methods and apparatuses for plowassemblies and more specifically to methods and apparatuses forsupporting a plow blade to a vehicle so that it is maintained in a levelorientation even when the plow blade is both raised and movedside-to-side.

II. SUMMARY OF THE INVENTION

According to one embodiment of this invention, a plow assembly maycomprise a plow blade assembly comprising: a plow blade having a plowsurface that is suitable to contact and plow an associated plowablesubstance; and, a support assembly that supports the plow blade assemblyto an associated vehicle. The support assembly may comprise: (1) a bladesupport structure that is attached to the plow blade assembly and thatsupports the plow blade assembly to the support assembly; (2) a bladeheight adjustment mechanism that is operable to raise and lower theblade support structure and the plow blade assembly with respect to anassociated ground surface; and, (3) a blade side-to-side adjustmentmechanism comprising: (a) a first frame component comprising: a firstend attached to the blade support structure and defining a substantiallyvertical first pivot axis about which the blade support structure andthe plow blade assembly are pivotal together with respect to the firstframe component; and a second end; (b) a second frame componentcomprising: a first end defining a second substantially horizontal pivotaxis about which the second frame component is pivotal with respect tothe vehicle when the blade height adjustment mechanism operates to raiseand lower the blade support structure and the plow blade assembly; and asecond end; (c) at least a first power device that is operable to causethe blade support structure and the plow blade assembly to pivottogether about the first pivot axis; and, (d) wherein the second end ofthe first frame component is pivotally attached to the second end of thesecond frame component about a substantially horizontal third pivot axisso that the first frame component, the blade support structure and theplow blade assembly are automatically pivotal together about the thirdpivot axis to maintain the plow blade in a level orientation when: (i)the blade height adjustment mechanism is operated to raise the bladesupport structure and the plow blade assembly with respect to theassociated ground surface; and, (ii) the first power device is operatedto cause the blade support structure and the plow blade assembly topivot together about the first pivot axis.

According to another embodiment of this invention, a plow assembly maycomprise a plow blade assembly comprising: a plow blade having a plowsurface that is suitable to contact and plow an associated plowablesubstance; and, a support assembly that supports the plow blade assemblyto an associated vehicle. The support assembly may comprise: (1) a bladesupport structure that is attached to the plow blade assembly and thatsupports the plow blade assembly to the support assembly; (2) a bladeheight adjustment mechanism that is operable to raise and lower theblade support structure and the plow blade assembly with respect to anassociated ground surface; and, (3) a blade side-to-side adjustmentmechanism comprising: (a) a first frame component comprising: a firstend attached to the blade support structure and defining a first pivotaxis about which the blade support structure and the plow blade assemblyare pivotal together with respect to the first frame component; and asecond end; (b) a second frame component comprising: a first enddefining a second pivot axis about which the second frame component ispivotal with respect to the vehicle when the blade height adjustmentmechanism operates to raise and lower the blade support structure andthe plow blade assembly; and a second end; (c) at least a first powerdevice that is operable to cause the blade support structure and theplow blade assembly to pivot together about the first pivot axis; and,(d) wherein the second end of the first frame component is pivotallyattached to the second end of the second frame component about a thirdpivot axis so that the first frame component, the blade supportstructure and the plow blade assembly are pivotal together about thethird pivot axis.

According to one embodiment of this invention, a method of maintaining aplow blade in a level orientation may comprise the steps of: (A)providing a plow assembly comprising: (I) a plow blade assemblycomprising: a plow blade having a plow surface that is suitable tocontact and plow an associated plowable substance; and, (II) a supportassembly that supports the plow blade assembly to an associated vehicle,the support assembly comprising: (1) a blade support structure that isattached to the plow blade assembly and that supports the plow bladeassembly to the support assembly; (2) a blade height adjustmentmechanism; (3) a blade side-to-side adjustment mechanism comprising: (a)a first frame component comprising: a first end attached to the bladesupport structure and defining a first pivot axis; and a second end; (b)a second frame component comprising: a first end defining a second pivotaxis; and a second end; (c) at least a first power device; and, (d)wherein the second end of the first frame component is pivotallyattached to the second end of the second frame component about a thirdpivot axis; (B) operating the blade height adjustment mechanism to pivotthe second frame component about the second pivot axis and to raise theblade support structure and the plow blade assembly with respect to anassociated ground surface; (C) operating the first power device to causethe blade support structure and the plow blade assembly to pivottogether about the first pivot axis with respect to the first framecomponent; and, (D) maintaining the plow blade in a level orientation byautomatically pivoting the first frame component, the blade supportstructure and the plow blade assembly together about the third pivotaxis with respect to the second frame component.

III. BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take physical form in certain parts and arrangement ofparts, embodiments of which will be described in detail in thisspecification and illustrated in the accompanying drawings which form apart hereof and wherein:

FIG. 1 is a perspective front view of a vehicle equipped with a plowassembly.

FIG. 2 is a side perspective close-up view of the vehicle and plowassembly shown in FIG. 1.

FIG. 3 is a top perspective close-up view of the plow assembly shown inFIG. 1.

FIG. 4 is a perspective side close-up view of the plow assembly shown inFIG. 1.

FIG. 5 is a side perspective schematic view of the lift mechanism shownin FIG. 1 with the chain represented as a pair of rods.

FIG. 6 is a top perspective view of a support frame.

FIG. 7 is a bottom perspective view of the first frame component.

FIG. 8 is a top perspective view of the first frame component.

FIG. 9 is a view taken along the line 9-9 of FIG. 8.

FIG. 10 is a view taken along the line 10-10 of FIG. 8.

FIG. 11 is a top perspective view of the second frame component.

FIG. 12 is a view taken along the line 12-12 of FIGURE

FIG. 13 is an end view of the second frame component of FIG. 11.

FIG. 14 is a perspective view of a clevis.

FIG. 15 is a top view of the clevis of FIG. 16.

FIG. 16 is a side view of the clevis of FIG. 16.

FIG. 17 is a perspective end view of a support frame according toanother embodiment.

FIG. 18 is a side perspective view of the support frame shown in FIG.17.

FIG. 19 is an end view of the support frame shown in FIG. 17.

FIG. 20 is a view similar to that shown in FIG. 17 but it shows thefirst frame component rotated relative to the second frame component.

FIG. 21 shows a support frame according to yet another embodiment.

IV. DETAILED DESCRIPTION

Referring now to the drawings wherein the showings are for purposes ofillustrating embodiments of the invention only and not for purposes oflimiting the same, and wherein like reference numerals are understood torefer to like components, FIG. 1 shows a vehicle 10 equipped with a plowassembly 30 according to one embodiment of this invention. While thevehicle shown is commonly known as a pick-up truck, it should beunderstood that the plow assembly 30 of this invention will work wellwith any vehicle chosen with the sound judgment of a person of skill inthe art. The plow assembly 30 may include a plow blade assembly 32 and asupport assembly 34 that supports the plow blade assembly 32 to thevehicle 10. The plow blade assembly 32 has a plow blade 36 with a plowsurface 38 that is suitable to be used to contact and plow snow, ice orthe like as is well known to those of skill in the art. However, itshould be understood that the plow assembly of this invention can beused with plow blades that are suitable to be used to contact and plowany plowable substance, such soil, chosen with the sound judgment of aperson of skill in the art. While the plow blade 36 shown is of aspecific type and shape, it should be understood that any plow bladechosen with the sound judgment of a person of skill in the art will workwell with this invention.

With reference now to FIGS. 1, 2 and 5, the support assembly 34 mayinclude a blade support structure 40, a blade height adjustmentmechanism 42, and a blade side-to-side adjustment mechanism 44. Theblade support structure 40 may have a distal (away from the vehicle)side to which the plow blade assembly 32 attaches. One or more tabs 46may extend from the distal side and receive pins 48 that hold the plowblade assembly 32 to the support assembly 34. For the embodiment shown,the pins 48 also define a pivot axis A5 about which the plow bladeassembly 32 can pivot or “trip” as is well known to those of skill inthe art.

With reference now to FIGS. 1-5, the blade height adjustment mechanism42 may include a lift frame 50 having a proximal (near the vehicle) endwith one or more attachment brackets 52 which attach to the vehicle in aknown manner. A lift arm 54 may have a proximal end pivotally attached,about generally horizontal and perpendicular to the length of the plowassembly 30 pivot axis Al, to the distal end of the lift frame 50. Thelift arm 54 may extend distally from the distal end of the lift frame50, as shown. A middle portion of a chain 56 may attach to the distalend of the lift arm 54 (such as via openings 58) and the opposite endsof the chain 56 may extend downwardly and attach to the blade supportstructure 40, as shown. Alternatively, two separate chains could beused. A power device or ram 60. such as hydraulic cylinder, may beconnected between the lift frame 50 and the lift arm 54. as shown. Inother embodiments, the power device may comprise a pneumatic cylinder oran electric motor. When the power device 60 is extended, the lift arm 54pivots in direction D1 and exerts a lift force (tension) onto the chain56 which cause the blade support structure 40 (and the plow bladeassembly 32) to be lifted. When the power device 60 is contracted, thelift arm 54 pivots in the opposite direction which permits the bladesupport structure 40 (and the plow blade assembly 32) to be lowered. Asthe operation of a power device with a plow blade is well known to thoseof skill in the art, further details will not be provided here.

With reference now to FIGS. 2, 5 and 6, the blade side-to-sideadjustment mechanism 44 may include a support frame 64 having a proximalend that pivots with respect to the vehicle 10. For the embodimentshown, the support frame 64 includes one or more attachment brackets 66which pivotally attach, about a generally horizontal and perpendicularto the length of the plow assembly 30 pivot axis A2, to the lift frame50, as shown. Alternatively, the proximal end of the support frame 64could be pivotally attached to the vehicle. The distal end of thesupport frame 64 may have one or more attachment brackets 70 withpivotally attach, about a generally vertical axis A3, to the bladesupport structure 40. This permits the blade support structure 40 (andthus the plow blade assembly 32) to be pivoted about axis A3 from sideto side. The blade support structure 40 may have one or more (two shown)contact surface 68 that contact the support frame 64 to limit the degreeof pivoting about axis A3.

With reference now to FIGS. 2 and 5-10, the support frame 64 may be anA-frame (a frame shaped like the letter A), as shown. Unlike knownsupport frames, however, support frame 64 is made of two primary framecomponents that are moveable relative to each other. Specifically, thesupport frame 64 shown has a first frame component 72 positionedrelatively distally and a second frame component 74 positionedrelatively proximally. The first frame component 72 includes theattachment brackets 70, 70 (two shown) which may have bushings 76 withopenings 78 that receive a pivot pin 80 that is received in at least oneopening in the blade support structure 40 and that defines the generallyvertical pivot axis A3. The attachment brackets 70, 70 may “sandwich”the top and bottom surfaces of the blade support structure 40. The firstframe component 72 may include a pair of tubes 82, 82 that form aV-shape with the distal ends attached to the attachment brackets 70, 70,as shown. A plate 84 may be attached to the proximal end of the firstframe component 72. The plate 84 may have a pair of tabs 86, 86extending from opposite sides of the first frame component 72, as shown.To provide further support and stability, atop and bottom plate 88, 90may attached to the first frame component 72.

With reference now to FIGS. 2, 5-6 and 10-13, the second frame component74 includes the attachment brackets 66, 66 which may extend proximallyfrom an angle member 94 and which may have openings 92, 92 that receivepivot pins defining the pivot axis A2. A pair of tubes 96, 96 may form aV-shape and have proximal ends attached to the angle member 94. Thedistal ends of the tubes 96, 96 may be attached to a plate 98. Onto eachside of the plate 98 at least one contact surface 101 may be provided.For the embodiment shown, each side of the plate 98 has a bracket 100fixed thereto with an opening 102. Surfaces of the bracket 100 definingthe opening 102 define two contact surfaces 101, 101 on the top andbottom of the opening 102, as indicated in FIG. 12. The plate 98 andbrackets 100, 100 may be sized such that the plate 84 is positionedjuxtaposed to the plate 98 and the tabs 86, 86 are received within theopenings 102, 102. The height of each opening 102 may be greater thanthe height of each tab 86 so that relative motion is possible. In oneembodiment, shown in FIGS. 11-12, the brackets 100 have an eventhickness around the openings 102. In another embodiment, seen best inFIG. 18, one side 101A of the bracket 101 has a curved outer surface toprovide additional strength.

With continuing reference to FIGS. 2, 5-6 and 10-13, the plate 98 mayhave a hole 104 and the plate 84 may have a hole 106. The holes 104, 106may be positioned concentrically and receive a pivot pin 108 (mostvisible in FIG. 18) that defines a generally horizontal and parallel tothe length of the plow assembly 30 pivot axis A4. In this way, the firstframe component 72 is relatively pivotal with respect to the secondframe component 74 about pivot axis A4. The top and bottom surfaces ofthe tabs 86 contact the contact surfaces to limit the relative pivotalmotion in both rotational directions. The design shown is capable ofproviding about 12 degrees of relative pivoting of the first framecomponent 72 with respect to the second frame component 74. Otherrelative degrees of relative pivoting are easily attainable, as known bythose of skill in the art. In an alternate embodiment, one or morecontact surfaces 101 are provided on the first frame component 72 andone or more tabs are provided on the second frame component 74.

With reference now to FIGS. 2, 4-6, and 14-16 at least one power deviceor ram 110 (two shown), such as a hydraulic cylinder, may be connectedbetween the second frame component 74 and the blade support structure40. In other embodiments, the power device may comprise a pneumaticcylinder, an electric motor, or a biasing member such as a spring. Forthe embodiment shown, the proximal ends of the power devices 110, 110are attached to a pair of attachment brackets 112, 112 on opposite sidesof the second frame component 74 and the distal ends of the powerdevices 110, 110 are attached to a pair of attachment brackets 114 onthe blade support structure 40. A clevis 116 may be used for each ofthese four attachments thus providing each end of each cylinder 110 withthe capability of pivoting relatively both about a generally horizontaland perpendicular to the length of the plow assembly 30 pivot axis andabout a generally vertical pivot axis.

With reference now to all the FIGURES, one advantage of this inventionis realized when mounting and dismounting. It is well known for theground surface upon which the plow assembly 30 is stored to be uneven.As a result, the elevation of the wheels on the vehicle (to which theplow assembly 30 is to be mounted) may be different that the elevationof the plow assembly 30. The relative motion permitted between the firstframe component 72 and the second frame component 74, which occursautomatically, minimizes this problem.

Another advantage of this invention is realized when the plow bladeassembly 32 is raised/lifted. The relative motion permitted between thefirst frame component 72 and the second frame component 74 allow theplow blade assembly 32 to remain substantially flat or level (at thesame elevation) when it is raised/lifted (off the ground) and pivotedfrom side to side. Prior to this invention, lifting and side-to-sidepivoting of known plow blade assemblies causes one end of the plow bladeassembly to dip or drop in elevation. This creates a greater likelihoodof inadvertently striking an object (including the ground) with thedipping edge of the plow blade. Suppose, for example, that the plowblade assembly 32 is in the position shown in FIG. 1, raised and angledgenerally straightforward. Suppose further that the operator thenactivates the controls to cause the plow blade assembly 32 to pivot toone side. Before this invention, such action by the operator would causeone end of the plow blade assembly 32 to dip. With this invention,however, such dipping does not occur. Instead, when the forces exertedon the blade support structure 40 by the chain 56 become uneven (thisoccurs when the side-to-side motion occurs) the first frame component 72automatically pivots with respect to the second frame component 74 andthe dipping is eliminated (or greatly minimized). Because of the use ofthe clevises 116, this relative motion of the first frame component 72with respect to the second frame component 74 does no damage to thecylinders 110 as they easily accommodate to the corresponding differingelevations at the distal ends of the cylinders 110.

Yet another advantage of this invention is realized when the plow isused on an uneven surface. If the ground surface is angled to one sideor undulates during plowing, the relative motion permitted between thefirst frame component 72 and the second frame component 74 allows theplow blade assembly 32 to automatically follow the ground surfacecontour.

FIGS. 17-20 show another embodiment. For this embodiment, the supportframe 64 includes first and second frame components 72, 74 each havingplates 84, 98, respectively, that are pivotal about pivot pin 108, aswith previously described embodiments. However, this embodiment alsoincludes an additional component(s) to maintain the plates 84, 98 in theproper relative position. Specifically, at least one bracket 130, twoshown, “sandwich” the plates 84, 98 to maintain the proper relativeposition. The brackets 130, 130 may be positioned substantiallyequidistant from the longitudinal axis of the frame 64, as shown. In oneembodiment, shown. the brackets 130 are fixed to the plate 98 but aremovable with respect to the plate 84. This can be seen by comparing FIG.17 to FIG. 20. In another embodiment, the brackets 130 are fixed to theplate 84 but are movable with respect to the plate 98. Each plate 84, 98may have a tab 132, 134 respectively, extending from their uppersurface, as shown. These tabs 132, 134 would contact the brackets 130,130 if the side-to-side relative position of the plates 84, 98 was toogreat. In this way, the brackets 130, 130 and tabs 132, 134 togetherwork as a “stop” to prevent undesirable relative motion.

FIG. 21 shows another embodiment where once again the support frame 64includes first and second frame components 72, 74 each having plates 84,98, respectively, that are pivotal about pivot pin 108. This embodimentuses a bracket 136 with an opening 138 that receives the tabs 132, 134(similar to those shown in FIGS. 17-20) to prevent undesirable relativemotion between the plates 84, 98 in a manner similar to the brackets130, 130 discussed above.

Numerous embodiments have been described, hereinabove. It will beapparent to those skilled in the art that the above methods andapparatuses may incorporate changes and modifications without departingfrom the general scope of this invention. It is intended to include allsuch modifications and alterations in so far as they come within thescope of the appended claims or the equivalents thereof.

Having thus described the invention, it is now claimed:

I/we claim:
 1. A plow assembly comprising: a plow blade assemblycomprising: a plow blade having a plow surface that is suitable tocontact and plow an associated plowable substance; and, a supportassembly that supports the plow blade assembly to an associated vehicle,the support assembly comprising: (1) a blade support structure that isattached to the plow blade assembly and that supports the plow bladeassembly to the support assembly; (2) a blade height adjustmentmechanism that is operable to raise and lower the blade supportstructure and the plow blade assembly with respect to an associatedground surface; and, (3) a blade side-to-side adjustment mechanismcomprising: (a) a first frame component comprising: a first end attachedto the blade support structure and defining a substantially verticalfirst pivot axis about which the blade support structure and the plowblade assembly are pivotal together with respect to the first framecomponent; and a second end; (b) a second frame component comprising: afirst end defining a second substantially horizontal pivot axis aboutwhich the second frame component is pivotal with respect to the vehiclewhen the blade height adjustment mechanism operates to raise and lowerthe blade support structure and the plow blade assembly; and a secondend; (c) at least a first power device that is operable to cause theblade support structure and the plow blade assembly to pivot togetherabout the first pivot axis; and, (d) wherein the second end of the firstframe component is pivotally attached to the second end of the secondframe component about a substantially horizontal third pivot axis sothat the first frame component, the blade support structure and the plowblade assembly are automatically pivotal together about the third pivotaxis to maintain the plow blade in a level orientation when: (i) theblade height adjustment mechanism is operated to raise the blade supportstructure and the plow blade assembly with respect to the associatedground surface; and. (ii) the first power device is operated to causethe blade support structure and the plow blade assembly to pivottogether about the first pivot axis.
 2. The plow assembly of claim 1wherein: the second end of the first frame comprises one of a first taband a first contact surface; the second end of the second framecomprises the other of the first tab and the first contact surface; and,the first tab contacts the first contact surface to limit the pivotalmotion of the first frame component, the blade support structure and theplow blade assembly about the third pivot axis.
 3. The plow assembly ofclaim 2 wherein: the second end of the first frame comprises a firstplate having a first hole and first and second ends; the second end ofthe second frame comprises a second plate having a second hole and firstand second ends; the first plate is juxtaposed to the second plate withthe first and second holes being substantially concentric and receivinga pivot pin that defines the third pivot axis; a first bracket having afirst opening is positioned on one of the first end of the first plateand the first end of the second plate, a first surface of the firstbracket defining the first opening defines the first contact surface anda second surface of the first bracket defining the first opening definesa second contact surface; the first tab is positioned on the other ofthe first end of the first plate and the first end of the second plate;the first tab is received in the first opening; the first tab contactsthe first contact surface to limit the pivotal motion of the first framecomponent, the blade support structure and the plow blade assembly aboutthe third pivot axis in a first rotational direction; and, the first tabcontacts the second contact surface to limit the pivotal motion of thefirst frame component the blade support structure and the plow bladeassembly about the third pivot axis in a second rotational directionthat is opposite the first rotational direction.
 4. The plow assembly ofclaim 3 wherein: a second bracket having a second opening is positionedon one of the second end of the first plate and the second end of thesecond plate, a first surface of the second bracket defining the firstopening defines a third contact surface and a second surface of thesecond bracket defining the first opening defines a fourth contactsurface; a second tab is positioned on the other of the second end ofthe first plate and the second end of the second plate; the second tabis received in the second opening; the second tab contacts the thirdcontact surface to limit the pivotal motion of the first framecomponent, the blade support structure and the plow blade assembly aboutthe third pivot axis in the first rotational direction; and, the secondtab contacts the fourth contact surface to limit the pivotal motion ofthe first frame component, the blade support structure and the plowblade assembly about the third pivot axis in the second rotationaldirection.
 5. The plow assembly of claim 4 wherein the second pivot axisis substantially perpendicular to the third pivot axis.
 6. The plowassembly of claim 5 wherein the first and second frame componentstogether form an A-frame.
 7. A plow assembly comprising: a plow bladeassembly comprising: a plow blade having a plow surface that is suitableto contact and plow an associated plowable substance; and, a supportassembly that supports the plow blade assembly to an associated vehicle,the support assembly comprising: (1) a blade support structure that isattached to the plow blade assembly and that supports the plow bladeassembly to the support assembly; (2) a blade height adjustmentmechanism that is operable to raise and lower the blade supportstructure and the plow blade assembly with respect to an associatedground surface; and, (3) a blade side-to-side adjustment mechanismcomprising: (a) a first frame component comprising: a first end attachedto the blade support structure and defining a first pivot axis aboutwhich the blade support structure and the plow blade assembly arepivotal together with respect to the first frame component; and a secondend; (b) a second frame component comprising: a first end defining asecond pivot axis about which the second frame component is pivotal withrespect to the vehicle when the blade height adjustment mechanismoperates to raise and lower the blade support structure and the plowblade assembly; and a second end; (c) at least a first power device thatis operable to cause the blade support structure and the plow bladeassembly to pivot together about the first pivot axis; and, (d) whereinthe second end of the first frame component is pivotally attached to thesecond end of the second frame component about a third pivot axis sothat the first frame component, the blade support structure and the plowblade assembly are pivotal together about the third pivot axis.
 8. Theplow assembly of claim 7 wherein: the first pivot axis is substantiallyvertical with respect to the associated ground surface; the second pivotaxis is substantially horizontal with respect to the associated groundsurface; and, the third pivot axis is substantially horizontal withrespect to the associated ground surface.
 9. The plow assembly of claim8 wherein the second pivot axis is substantially perpendicular to thethird pivot axis.
 10. The plow assembly of claim 7 wherein the first andsecond frame components together form an A-frame.
 11. The plow assemblyof claim 7 wherein: the second end of the first frame comprises one of afirst tab and a first contact surface; the second end of the secondframe comprises the other of the first tab and the first contactsurface; and, the first tab contacts the first contact surface to limitthe pivotal motion of the first frame component, the blade supportstructure and the plow blade assembly about the third pivot axis. 12.The plow assembly of claim 11 wherein: the second end of the first framecomprises one of: first and second brackets defining the first contactsurface and a second contact surface; and, the first tab and a secondtab; the second end of the second frame comprises the other of: thefirst and second brackets defining the first and second contactsurfaces; and, the first and second tabs; the first tab contacts thefirst contact surface to limit the pivotal motion of the first framecomponent, the blade support structure and the plow blade assembly aboutthe third pivot axis in a first rotational direction; and, the secondtab contacts the second contact surface to limit the pivotal motion ofthe first frame component, the blade support structure and the plowblade assembly about the third pivot axis in a second rotationaldirection that is opposite the first rotational direction.
 13. The plowassembly of claim 11 wherein: the second end of the first framecomprises a first plate having first and second ends; the first tab ispositioned on the first end of the first plate; the second end of thesecond frame comprises a second plate having first and second ends; afirst bracket having a first opening is positioned on the first end ofthe second plate; a first surface of the first bracket defining thefirst opening defines the first contact surface and a second surface ofthe first bracket defining the first opening defines a second contactsurface; the first plate is juxtaposed to the second plate; the firsttab is received in the first opening; the first tab contacts the firstcontact surface to limit the pivotal motion of the first framecomponent, the blade support structure and the plow blade assembly aboutthe third pivot axis in a first rotational direction; and, the first tabcontacts the second contact surface to limit the pivotal motion of thefirst frame component, the blade support structure and the plow bladeassembly about the third pivot axis in a second rotational directionthat is opposite the first rotational direction.
 14. The plow assemblyof claim 11 wherein: the second end of the first frame comprises a firstplate having first and second ends; the first tab is positioned on thefirst end of the first plate; a second tab is positioned on the secondend of the first plate; the second end of the second frame comprises asecond plate having first and second ends; a first bracket having afirst opening is positioned on the first end of the second plate; afirst surface of the first bracket defining the first opening definesthe first contact surface; a second bracket having a second opening ispositioned on the second end of the second plate; a second surface ofthe second bracket defining the second opening defines a second contactsurface; the first plate is juxtaposed to the second plate; the firsttab is received in the first opening; the second tab is received in thesecond opening; the first tab contacts the first contact surface tolimit the pivotal motion of the first frame component, the blade supportstructure and the plow blade assembly about the third pivot axis in afirst rotational direction; and. the second tab contacts the secondcontact surface to limit the pivotal motion of the first framecomponent, the blade support structure and the plow blade assembly aboutthe third pivot axis in a second rotational direction that is oppositethe first rotational direction.
 15. A method of maintaining a plow bladein a level orientation comprising the steps of: (A) providing a plowassembly comprising: (I) a plow blade assembly comprising: a plow bladehaving a plow surface that is suitable to contact and plow an associatedplowable substance; and, (II) a support assembly that supports the plowblade assembly to an associated vehicle, the support assemblycomprising: (1) a blade support structure that is attached to the plowblade assembly and that supports the plow blade assembly to the supportassembly; (2) a blade height adjustment mechanism; (3) a bladeside-to-side adjustment mechanism comprising: (a) a first framecomponent comprising: a first end attached to the blade supportstructure and defining a first pivot axis; and a second end; (b) asecond frame component comprising: a first end defining a second pivotaxis; and a second end; (c) at least a first power device; and, (d)wherein the second end of the first frame component is pivotallyattached to the second end of the second frame component about a thirdpivot axis; (B) operating the blade height adjustment mechanism to pivotthe second frame component about the second pivot axis and to raise theblade support structure and the plow blade assembly with respect to anassociated ground surface; (C) operating the first power device to causethe blade support structure and the plow blade assembly to pivottogether about the first pivot axis with respect to the first framecomponent; and, (D) maintaining the plow blade in a level orientation byautomatically pivoting the first frame component, the blade supportstructure and the plow blade assembly together about the third pivotaxis with respect to the second frame component.
 16. The method of claim15 wherein step (A) comprises the steps of: providing the first pivotaxis to be substantially vertical with respect to the associated groundsurface; providing the second pivot axis to be substantially horizontalwith respect to the associated ground surface; and, providing the thirdpivot axis to be substantially horizontal with respect to the associatedground surface and substantially perpendicular with respect to thesecond pivot axis.
 17. The method of claim 15 wherein: step (A)comprises the steps of: providing the second end of the first frame tocomprise one of a first tab and a first contact surface; and, providingthe second end of the second frame to comprise the other of the firsttab and the first contact surface; and, step (D) comprises the step of:limiting the pivoting of the first frame component, the blade supportstructure and the plow blade assembly together about the third pivotaxis with respect to the second frame component by contacting the firsttab with the first contact surface.
 18. The method of claim 17 wherein:step (A) comprises the steps of: (1) providing the second end of thefirst frame with one of: first and second brackets defining the firstcontact surface and a second contact surface; and, the first tab and asecond tab; and, (2) providing the second end of the second frame withthe other of: the first and second brackets defining the first andsecond contact surfaces; and, the first and second tabs; and, step (D)comprises at least one of: (1) contacting the first tab to the firstcontact surface to limit the pivotal motion of the first framecomponent, the blade support structure and the plow blade assembly aboutthe third pivot axis in a first rotational direction; and, (2)contacting the second tab to the second contact surface to limit thepivotal motion of the first frame component, the blade support structureand the plow blade assembly about the third pivot axis in a secondrotational direction that is opposite the first rotational direction.19. The method of claim 17 wherein: step (A) comprises the steps of: (1)providing the second end of the first frame with a first plate havingfirst and second ends; (2) providing the first tab to be positioned onthe first end of the first plate; (3) providing the second end of thesecond frame with a second plate having first and second ends; (4)providing a first bracket having a first opening that defines the firstcontact surface and also defines a second contact surface on the firstend of the second plate; (5) juxtaposing the first plate to the secondp)ate; and, (6) positioning the first tab in the first opening; and,step (D) comprises at least one of: (1) contacting the first tab to thefirst contact surface to limit the pivotal motion of the first framecomponent, the blade support structure and the plow blade assembly aboutthe third pivot axis in a first rotational direction; and, (2)contacting the first tab to the second contact surface to limit thepivotal motion of the first frame component, the blade support structureand the plow blade assembly about the third pivot axis in a secondrotational direction that is opposite the first rotational direction.20. The method of claim 17 wherein: step (A) comprises the steps of: (1)providing the second end of the first frame with a first plate havingfirst and second ends; (2) providing the first tab on the first end ofthe first plate; (3) providing a second tab on the second end of thefirst plate; (3) providing the second end of the second frame with asecond plate having first and second ends; (4) providing a first brackethaving a first opening that defines the first contact surface on thefirst end of the second plate; (5) providing a second bracket having asecond opening that defines a second contact surface on the second endof the second plate; (6) juxtaposing the first plate to the secondplate; (7) positioning the first tab in the first opening; and, (8)positioning the second tab in the second opening; and, step (D)comprises at least one of: (1) contacting the first tab to the firstcontact surface to limit the pivotal motion of the first framecomponent, the blade support structure and the plow blade assembly aboutthe third pivot axis in a first rotational direction; and, (2)contacting the second tab to the second contact surface to limit thepivotal motion of the first frame component, the blade support structureand the plow blade assembly about the third pivot axis in a secondrotational direction that is opposite the first rotational direction.